Known refrigeration gas compressors of the type useful in household and industrial refrigeration systems are generally heavy and quite bulky in size, considering their volume and compression characteristics. Besides being inherently inefficient, reciprocating piston compressors are not only relatively heavy and bulky but also rather noisy in operation due to vibration which can be exacerbated by the required crankshaft and connecting rods. Rotary compressors overcome the noise and vibration problems to an extent, but sacrifice efficiency as a result due to large area rubbing surfaces creating heat, friction and wear during operation.
The present invention combines the more desirable characteristics of reciprocating piston compressors and rotary compressors to produce a rotary-reciprocating piston compressor of relatively simple design, low in number of moving parts and having high volume and compression characteristics with respect to weight and size of the compressor, when compared to known prior art compressors.
The very broad concept of combining rotary and reciprocating piston characteristics is known in the art of internal combustion engines, at least. Specifically, U.S. Pat. No. 1,166,999 discloses an internal combustion engine having a rotor with circumferentially arranged compression slots successively entered by compressors in the form of rollers mounted on an axis parallel to but offset from the rotor axis. A steam engine of similar design is disclosed in U.S. Pat. Ser. No. 726,896. Another engine of similar design powered by compressed gas is disclosed in U.S. Pat. Ser. No. 726,157.
However, the prior art does not disclose a rotary-reciprocating piston compressor having the characteristics of the present invention as set forth below.